@anoek thank you for your hard work.
Assuming most new players are new at go as well, this would stabilize the rating of new players around 1500. Glicko separates players only relative to each other. A supposed 25k would win about 50% of her games against her fellow 25ks, leading Glicko to decide that both players are rated correct, leafing both at 1500, lowering only their deviation.
Maybe it’s mean. It’s neither median nor mode. But at least over time there would be rank deflation if one changes the entry point for all new players. To balance 3 entry points in a way that prevents inflation/deflation would be a real hassle.
The Glicko2 specification fixes the entry point to one value (not talking about guessing initial ranks of new players)
(a) If the player is unrated, set the rating to 1500 and the RD to 350. Set the player’s volatility to 0.06 (this value depends on the particular application).
(b) Otherwise, use the player’s most recent rating, RD, and volatility σ.
@smurph
I cannot recalculate the whole rating pool. I don’t get the ratings of GnuGo and Master Mantis stable. At some point in time their rating starts to skyrocket. They played to many games to just ignore them.
And I don’t understand what you want me to do anyways. Change the initial rating of some players and see what happens?